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AIMS AND OBJECTIVES To identify determinants of quality of life among patients who had experienced hypoglycaemia and who were undergoing insulin treatment. BACKGROUND Patients with diabetes receiving insulin treatment are at high risk for hypoglycaemia, which tends to affect their quality of life. DESIGN With a cross-sectional and observational study design (see the STROBE checklist and Appendix S1). METHODS One hundred and fifty patients with type 2 diabetes who had received insulin treatment and had experienced hypoglycaemia ( more...

The impact of different temporal resolutions of rainfall data on the Biosphere assessment for radioactive waste disposal in the tropical monsoon region with concentrated rainfall is evaluated in this research. Two scenarios are considered to verify the effect of release location. A simplified surface water budget model is used to generate the surface water flow rates for the biosphere model, which is implemented using three different temporal averaging intervals to consider the uncertainty caused by short-term impact. Kaohsiung in Taiwan is chosen as an example because of its extreme rainfall distribution. The results show that it is improper to use the annual rainfall data for this case, and it is suggested to consider a 20% margin to cover the underestimation of dose if the monthly rainfall data are used. The results of the biosphere models built with different timesteps show that a non-negligible difference occurs for radionuclides with a low Kd value in the river water release scenario and no difference for the well water release scenario. more...

In this paper, a loading pattern strategy In-Cycle-Shuffle (ICS) is implemented to the last cycle of the boiling water reactor (BWR) before decommissioning to save the fuel cycle cost. This method needs a core shutdown during the operation of a cycle to change the loading pattern to gain more reactivity. The reactivity model is used to model the ICS strategy in order to find out the best ICS timing and the optimum power sharing distribution before ICS and after ICS. Several parameters of reactivity model are modified and the effect of burnable poison, gadolinium (Gd), is considered in this research. Three cases are presented and it is found that the best ICS timing is at about two-thirds of total cycle length no matter the poisoning effect of Gd is considered or not. According to the optimum power sharing distribution result, it is suggested to decrease the once burnt power and increase the thrice burnt fuel power as much as possible before ICS. After ICS, it is suggested to increase the positive reactivity fuel power and decrease the thrice burnt fuel power as much as possible. A new parameter “Burnup sharing” is presented to evaluate the special case whose EOC power weighting factor and the burnup accumulation factor in the reactivity model are quite different. more...

Wireless power transmission system has been developing rapidly in recent years, and its application is becoming more and more extensive. In order to enhance the stability of the system operation, the communication module used in the transmitting and receiving terminals must be added to the system operation. The paper realizes the receiver and the transmitter chip to execute the signal transmission, which is different from the power transmission. Adopts the appropriate circuit design, the inband WPT system can be more stable and practical applying to various instruments of the wireless power transfer system. more...

A study of in-core power sharing and fuel requirement for a decommissioning BWR (Boiling Water Reactor) was carried out using the linear reactivity model (LRM). The power sharing of each fuel batch was taken as an independent variable, and the related parameters were set and modified to simulate actual cases. Optimizations of the last cycle and two cycles before decommissioning were both implemented; in the last-one-cycle optimization, a single cycle optimization was carried out with different upper limits of fuel batch power, whereas, in the two-cycle optimization, two cycles were optimized with different cycle lengths, along with two different optimization approaches which are the simultaneous optimization of two cycles (MO) and two successive single-cycle optimizations (SO). The results of the last-one-cycle optimization show that it is better to increase the fresh fuel power and decrease the thrice-burnt fuel power as much as possible. It also shows that relaxing the power limit is good to the fresh fuel requirement which will be reduced under lower power limit. On the other hand, the results of the last-two-cycle (cycle N-1 and N) optimization show that the MO is better than SO, and the power of fresh fuel batch should be decreased in cycle N-1 to save its energy for the next cycle. The results of the single-cycle optimization are found to be the same as that in cycle N of the multi-cycle optimization. Besides that, under the same total energy requirement of two cycles, a long-short distribution of cycle length design can save more fresh fuel. more...

In this study, a urea biosensor was prepared by the immobilization of urease onto the sensitive membrane of an extended-base bipolar junction transistor. The pH variation was used to detect the concentration of urea. The SnO2/ITO glass, fabricated by sputtering SnO2 on the conductive ITO glass, was used as a pH-sensitive membrane, which was connected with a commercial bipolar junction transistor device. The gels, fabricated by the poly vinyl alcohol with pendent styrylpyridinium groups, were used to immobilize the urease. This readout circuit, fabricated in a 0.35-um CMOS 2P4M process, operated at 3.3V supply voltage. This circuit occupied an area of 1.0 mm × 0.9 mm. The dynamic range of the urea biosensor was from 1.4 to 64 mg/dl at the 10 mM phosphate buffer solution and the sensitivity of this range was about 65.8 mV/pUrea. The effect of urea biosensors with different pH values was considered, and the characteristics of urea biosensors based on EBBJT were described. more...

The development of wireless power transfer for internet of things (IoT) application is proposed in this paper. For the IoT instrument, the delivered power dependents on the instrument load impedance and the coil distance. Hence, the transfer efficiency is determined by the load impedance and the coil distance. This paper investigates real instrument with different the load impedance and variation of the distance in magnetic resonance coils. To characterize the phenomenon, a circuit model is proposed to calculate the coil behavior in different load impedance and coil distance. Measurement result shows an optimal distance is obtained at a specified load impedance. more...

A wireless power transfer system operated at 6.78MHz for AirFuel specification is demonstrated in this paper. The system includes transceiver, receiver, magnetic resonance coil, and data communication. To monitor the transferred power, a communication path is establish by using the micro-controller, amplitude modulator/demodulator, and voltage/current sensing circuits. All of the modules are integrated in a printed circuit board and a micro-controller. The measurement shows the power is transfer with the coil distance is 6 cm and the efficiency is 35%. more...

It's an important topic that how to improve the illumination but decreasing or no increasing the electricity loads. The energy-efficient lighting equipment in the study was T5 lighting fixture combining with High-efficiency Reflector and Low-loss Diffuser Plate. The High-Efficiency Reflector could reflex the luminous energy above 97%. The illuminance could be improved largely through using the High-Efficiency Reflector without additional power. The High-Efficient Equipment illuminated the environment with low glare by the lights through the plate. Saving electricity was 47.5% and the measured illumination was increased more than 2 times in case one. The saving electricity was 30% and the measured illumination was increased about 1.5~2 times in case two. The specific benefits using energy-efficient lighting equipment were saving energy and enhance illumination. Cost of the investment achieved balance about 9.5~13.3 months. The additional value was a lighting environment with uniformity and low-glare. The energy-efficient lighting equipment could be an option of green construction. more...

The present study evaluates the toxicity of 34 propargylic alcohols, including primary, primary homo-, secondary, and tertiary alcohols, based on their effects on phytoplankton. A closed-system algal toxicity test was applied because the closed-system technique presents more realistic concentration-response relationships for the above compounds than the conventional batch tests. The green alga, Pseudokirchneriella subcapitata, was the test organism and final yield and growth rate were chosen as the test endpoints. Among all the propargylic alcohols tested, 1-pentyn-3-ol is the most toxic compound with its EC50 equal to 0.50 mg L(-1), which can be classified as a "R50" compound (very toxic to aquatic organisms, EC50/LC50 < 1 mg L(-1)), following the current practice for classification of chemicals in the European Union (EU). There are several other compounds including 2-decyn-1-ol, 3-decyn-1-ol, 1-hexyn-3-ol, 3-butyn-2-ol, and 3-hexyne-2,5-diol, which deserve more attention for their possible adverse impact on the aquatic environment, because these alcohols can be classified as "R51" compounds (toxic to aquatic organisms, EC50/LC50 between 1 and 10 mg L(-1)). Compared to the base-line toxicity relationship (narcosis QSAR) derived previously, tertiary propargylic alcohols can be identified as nonpolar narcotic chemicals, while secondary alcohols and primary alcohols with low molecular weight generally exhibit obvious excess toxicity in relation to the base-line toxicity. Finally, quantitative structure-activity relationships were established for deriving a preliminary estimation of the toxicity of other propargylic alcohols. more...

The objective of this study was to develop a ferrocene mediated glucose biosensor for reverse iontophoresis. An amperometric ferrocene mediated glucose biosensor based on a three electrodes planar configuration was constructed using screen printing technique. Different combinations of glucose oxidase and ferrocene loading were drop coated onto the surface of the amperometric transducer. The amperometric transducer was characterized electrochemically using cyclic voltammetry and its electrochemical characteristics (DeltaE(p) = 70 mV, I(pa)/I(pc) = 0.89) were found close to an ideal amperometric transducer. The biosensor on the detection of glucose at 200 mV (vs. Ag/AgCl) showed a linear response range (0-4 mM). The response time of the biosensor was about 10 s. Finally, the biosensor was used together with reverse iontophoresis technique. By the use of an actual model for evaluation, an excellent linear relationship (r(2) = 0.99) was found between the glucose concentration of the actual model and the biosensor current response. In conclusion, a ferrocene mediated glucose biosensor incorporated with reverse iontophoresis function was developed. more...

The effects of Bi4Ti3O12 addition on the microstructure and dielectric properties of Mn-modified BaTiO3 were investigated to develop low temperature fired BaTiO3-based ceramics with stable temperature characteristics. The sintering temperature of Mn-doped BaTiO3 could be reduced to 1200 °C by adding more than 1 mol% Bi4Ti3O12. TEM results show an apparent core–shell structure with 2 mol% Bi4Ti3O12 addition. However, it was destroyed when the Bi4Ti3O12 content increased from 2 to 4 mol%. The permittivity decreased and the Curie temperature shifted to higher temperature when the Bi4Ti3O12 content increased from 0 to 3 mol%. The temperature characteristic of capacitance was very close to the EIA X8R specification when 2 mol% Bi4Ti3O12 was added due to the presence of the core–shell grain structure and raised Curie temperature. With adequate Bi4Ti3O12 addition, the BaTiO3-based system shows great potential for applications in EIA X8R-type multilayer ceramic capacitors. more...

The no-observed-effect concentrations (NOEC) and EC(10) values for 108 organic compounds were estimated, using multiple endpoints (i.e., biopopulation, growth rate, and dissolved oxygen production), from previous data obtained by a closed-system algal toxicity test (test alga: Pseudokirchneriella subcapitata). These low-toxic-effect concentrations are valuable to risk assessment of chemicals and protection of the aquatic environment as such information is quite scarce in existing toxicological databases. Furthermore, based on limited amount of available data, we found that the risk of organic toxicants to phytoplankton may be severely underestimated by existing databases, which are primarily derived by the conventional batch technique. Good correlation relationships between NOEC (or EC(10)) and EC(50) values were established. For polar and nonpolar narcotics, quantitative structure-activity relationships (QSARs) based on hydrophobicity, and/or the lowest unoccupied molecular orbital energy (Elumo) were developed with satisfactory predictive powers. The above statistical relationships can be applied to derive a preliminary estimation for the low-toxic-effect levels for other (or new) organic compounds that has no toxicological data available. more...

The present study presents the toxicity data of benzoic acid and its derivatives on Pseudokirchneriella subcapitata, in terms of EC50 and NOEC values. Median effective concentrations (EC50) range from 0.55 to 270.7 mg/L (based on final yield) and 1.93 to 726.3mg/L (based on algal growth rate). No-observed-effect concentration (NOEC) is within the range of more...

The effects of Bi 4 Ti 3 O 12 on the microstructure and dielectric properties of Mn-doped BaTiO 3 were studied using X-ray diffraction (XRD) and transmission electron microscope (TEM). From XRD analysis and scanning electron microscope (SEM) observations, second phase Bi 2 Ti 2 O 7 was found when the Bi 4 Ti 3 O 12 content was more than 4 mol%. The grain size was significantly enhanced with increased Bi 4 Ti 3 O 12 content. The sintering temperature of Mn-doped BaTiO 3 -based ceramics could be reduced effectively to 1200 °C by doping them with more than 1 mol% Bi 4 Ti 3 O 12 . TEM results show an obvious core–shell structure with 2 mol% Bi 4 Ti 3 O 12 , which was destroyed when the Bi 4 Ti 3 O 12 content increased from 2 to 4 mol%. It was found that the Curie temperature was shifted to a higher level and the variation of dielectric constant decreased when Bi 4 Ti 3 O 12 content increased from 0 to 2 mol%. When the Bi 4 Ti 3 O 12 content was more than 2 mol%, the Curie temperature decreased due to a change of the core–shell structure and secondary phase Bi 2 Ti 2 O 7 . The variation of dielectric constant as compared with that at room temperature was about −25% at −55 °C and less than ±10% at 150 °C. The stable temperature characteristics of the dielectric constant were caused by the presence of the core–shell grain structure. Due to the “clockwise effect”, ceramic materials have great potential as EIA X8R-type multilayer ceramic capacitors. more...

We present molecular cloning and tissue expression analysis of three estrogen receptor (ER) subtypes, vbERalpha, vbERbeta1 and vbERbeta2, from liver of the cyprinid fish Varicorhinus barbatulus through reverse transcription-polymerase chain reaction (RT-PCR) and rapid amplification of cDNA ends (RACE). The sequence alignment and phylogenetic analysis reconfirmed the evolutionary relationship of V. barbatulus within the family Cypriniformes. Directional constraints for subtype-specific substitution of critical amino acids were observed in the E2 binding region. For amino acid substitution, vbERbeta exhibited a M517L change in the ligand-dependent transactivation region. The tissue distributions were investigated using RT-PCR with subtype-distinguishable primers. Both vbERalpha and vbERbeta1 were most highly expressed in liver, while vbERbeta2 was higher in intestine. Here we demonstrate that the identification and cloning of ER subtypes using PCR is feasible in wildlife in that the temporal and spatial observations are consistent with those from phylogeny analysis and crystal structural investigation by others. more...

This study evaluated the toxic effects of substituted anilines on Pseudokirchneriella subcapitata with the use of a closed algal toxicity testing technique with no headspace. Two response endpoints (i.e., dissolved oxygen production [DO] and algal growth rate) were used to evaluate the toxicity of anilines. Both DO and growth rate endpoints revealed similar sensitivity to the effects of anilines. However, trichloroanilines showed stronger inhibitory effects on microalgal photosynthetic reactions than that on algal growth. For various aquatic organisms, the relative sensitivity relationship for anilines is Daphnia magna > luminescent bacteria (Microtox) > or = Pocelia reticulata > or = Pseudokirchneriella subcapitata > or = fathead minnow > Tetrahymena pyriformis. The susceptibility of P. subcapitata to anilines is similar to fish, but P. subcapitata is apparently less sensitive than the water flea. The lack of correlation between the toxicity revealed by different aquatic organisms (microalgae, D. magna, luminescent bacteria, and P. reticulata) suggests that anilines might have different metabolic routes in these organisms. Both hydrogen bonding donor capacity (the lowest unoccupied molecular orbital energy, Elumo) and hydrophobicity (1-octanol:water partition coefficient, Kow) were found to provide satisfactory descriptions for the toxicity of polar narcotics (substituted anilines and chlorophenols). Quantitative structure-activity relationships (QSARs) based on Elumo, log Kow, or both values were established with r2 values varying from 0.75 to 0.92. The predictive power for the QSAR models were found to be satisfactory through leave-one-out cross-validation. Such relationships could provide useful information for the estimation of toxicity for other polar narcotic compounds. more...

This study presents the metal toxicity as revealed by Chlorella pyrenoidosa using a short-term continuous test and the conventional batch test. Toxicity tests were conducted in a chemostat with a test duration of 1 day. Toxicity data of five different metals (Cd, Pb, Co, Ni, and Zn) derived from the continuous test were compared against results from the conventional batch tests. The batch test is characterized by its saturated nutrient status for algal growth and, on the other hand, the continuous test is conducted at a nutrient-limiting condition simulating more closely to the aquatic field environment. The continuous test consistently yielded smaller EC(50) values, which indicated that alga in the chemostat is approximately four to six times more sensitive than those from the batch culture. Similar phenomena between the two types of tests were observed based on the NOEC values. Compared to literature data (US EPA ECOTOX Database) from the same species of alga, differences in test sensitivity between the batch tests and chemostat technique varied from 9.25 to 160 times. Such distinct differences indicate that current toxicity database may not adequately reflect the impact of various metal toxicants on C. pyrenoidosa. The continuous test method presented herein is a sensitive and rapid assessment technique and, therefore, has a potential for more general applications such as routine checkup for regulatory purposes. more...

The existing toxicity data on the effects of polycyclic aromatic hydrocarbons (PAHs) on Pseudokirchneriella subcapitata (green alga) are quite insufficient. These data were derived using different test techniques (e.g. conventional batch test, closed-system test, semi-static test). The relative toxicity relationship for various PAHs is thus difficult to interpret. Consequently, the current toxicity database is insufficient and also inadequate for analyses of the effects of PAHs on P. subcapitata. This study evaluated the toxicity of eleven PAHs using an air-tight test technique. The relative toxicity relationship was determined on a uniform basis, and was different from the relationship based on current available data. P. subcapitata. was found to be more susceptible to PAHs than Daphnia magna, fathead minnow, and Scenedesmus subspicatus. Quantitative structure-activity relationship (QSAR) was established based on the chemical's hydrophobicity with R2 equal to 0.88. Photo-induced toxicity for various PAHs was also explored by exposing PAHs under UV-photoactivation. Toxicity of anthracene, benzanthrone, and benzo[a]anthracene was found to increase 3.5 to 25 times after UV exposure. Phototoxicity was observed when the HOMO-LUMO gap varied between 6.8 and 8.0 eV. more...

Ba(Sn x Ti 1− x )O 3 (BS x T 1− x ) thin films prepared by radio frequency (RF) magnetron sputtering in a mixture of O 2 /Ar atmosphere have been characterized as a function of RF power. The BS x T 1− x thin films are amorphous when sputtered at RF power = 100 and 125 W. The XRD shows only single perovskite structure phase of BaTiO 3 . The intensity of reflection increases with RF power increases from 125 to 175 W. The BS x T 1− x thin films sputtered with RF power at 150 W produced maximum deposition. The effect of the RF power on the Sn/(Sn + Ti) ratio is not significant. The refractive index of the BS x T 1− x thin films increases with increasing RF power. The dielectric constant of the BS x T 1− x thin films increases with increasing Sn content for films sputtered at the same RF power. On the other hand, the dielectric constant of the BS x T 1− x thin films increases when the RF power is increased from 100 to 150 W, but the dielectric constant decreases for RF power greater than 150 W. more...

Ba(SnxTi1-x)O3 (BSxT1-x, 0≤x≤0.15) thin films deposited by rf magnetron sputtering with platinum (Pt) top and silver (Ag) bottom electrodes have been characterized with respect to the dielectric properties and leakage current density as a function of composition and rf power. BSxT1-x thin films are amorphous when deposited at rf powers of 100 and 125 W, 5×10-3 Torr working pressure, an O2/(O2+Ar) ratio of 1/(1+9) and room temperature. The XRD result shows the presence of a single perovskite phase of BaTiO3, operated at a range of rf power increasing from 125 to 175 W. The maximum capacitance of Pt/BSxT1-x/Si/Ag capacitors increases with increasing Sn content. The ferroelectric characteristics of the capacitance–voltage hystersis loop in the BSxT1-x thin films are observed. The leakage current density of the Pt/BS0.15T0.85/Si/Ag capacitors at 100 kV/cm varies from mid 10-6 to about 10-8 A/cm2 with the rf power decreasing from 175 to 125 W. The dominant conduction mechanism of the BS0.15T0.85 thin films has shown to be related to Schottky emission (SE) and Poole–Frenkel (PF) mechanisms. The remnant polarization (Pr) and coercive electric field (Ec) of the above device appear to decrease with increasing Sn content. more...

This paper presents the toxicity data of 10 nonpolar narcotic chemicals on Pseudokirchneriella subcapitata (green algae) assessed by a new algal toxicity testing technique conducted under air-tight environment. Based on DO production, median effective concentration (EC50) varies from 1.73 mg/L (1-octanol) to 8040 mg/L (2-propanol). The endpoint of algal growth rate reveals similar sensitivity as that from DO production. Compared to literature data, Pseudokirchneriella subcapitata and Nitrosomonas are apparently more sensitive to nonpolar narcotics than other organisms such as minnow, daphnia, and Tetrahymena pyriformis. Furthermore, good correlations between toxic effects observed from Pseudokirchneriella subcapitata and other aquatic organisms were found. Hence, algal toxicity test can be considered as a surrogate test for estimating the toxicity of nonpolar chemicals to fathead minnow, Microtox, activated sludge, Daphina magna, and Tetrahymena pyriformis. The combined effects of 13 binary mixtures of nonpolar chemicals were investigated using both additive-index method and isobologram analysis. Overall speaking, the joint actions between these chemicals are strictly additive. Model analyses indicate that these compounds act on identical reaction sites or receptors, which verify that these chemicals are of the same toxicity mechanism (narcosis). more...

This paper presents the toxicity data of seven pesticides including atrazine, parathion, dichlorvos, malathion, fenthion, 2-methyl-4-chlorophenoxyacetic acid, and pentachlorophenol on Pseudokirchneriella subcapitata based on a new algal toxicity testing technique conducted under air-tight environment. The dissolved oxygen production and the cell density were adopted as the response endpoints. Median effective concentrations (EC50) range from 0.0035 to 3.40 mg/L (DO production) and from 0.0067 to 3.12 mg/L (cell density). No-observed-effect concentration (NOEC) was determined using the Dunnett's test. NOEC values are with in the range of 0.001-1.20 mg/L. In general, the two test endpoints revealed similar sensitivities. From comparisons of literature data also based on Pseudokirchneriella subcapitata, it is clear that conventional batch tests tend to underestimate the toxicity of pesticides due to their open test environment. Closed-system tests, i.e., microplate test, respirometer test, and our BOD-bottle test, generally provide better assessment to the effects of pesticides. Data based on our test method reveals much higher toxicity (3-100 times) than that from the conventional batch tests. Furthermore, for organophosphorus insecticides, results from the present study show that Pseudokirchneriella subcapitata is less sensitive than Daphnia magna and rainbow trout, but is more susceptible than fathead minnow. The closed-system test applied in this study provides more adequate assessment for the toxicity of pesticides than the conventional batch tests. more...

A closed-system algal toxicity test with no headspace was applied to evaluate the toxicity of chlorophenols to Pseudokirchneriella subcapitata. The dissolved oxygen production and the growth rate based on cell density were the response endpoints. Phenol and seven chlorophenols were tested using the above test technique. Median effective concentrations (EC50) range from 0.004 to 25.93 mg/l (based on DO production) and 0.0134 to 20.90 mg/l (based on growth rate). No-observed-effect concentration (NOEC) is within the range of 0.001-8.19 mg/l. In general, growth rate is a more sensitive response endpoint than the oxygen production, except for the case of pentachlorophenol. However, the differences in sensitivity between the two parameters were marginal. Furthermore, quantitative structure-activity relationships (QSAR's) based on the n-octanol/water partition coefficient (log P) and the acid dissociation constant (pK(a)) values were established with R(2) ranged from 0.90 to 0.96. From literature data also based on P. subcapitata, the new test method is 1.65-108 times more sensitive than the conventional algal batch tests. A completely different relative-sensitivity relationship among various aquatic organisms was thus observed. The results of this study indicate that the toxicity data of volatile organic chemicals derived by conventional algal toxicity tests may severely underestimate the impact of these toxicants. Our results show that alga is very sensitive to chlorophenols compared to other aquatic organisms such as the luminescent bacteria (the Microtox test), Daphnia magna, and rainbow trout. more...

The growth rate and dielectric properties of the Ba(SnxTi1−x)O3 (BSxT1−x) thin films prepared by radio frequency (rf) magnetron sputtering at room temperature have been characterized as a function of deposition parameters. The BSxT1−x thin films are amorphous when deposited at low rf power (Rp = 100 and 125 W). The XRD result shows merely a single perovskite (BaTiO3) structure and the intensity of reflection peaks increases with the rf power increasing from 125 to 150 and 175 W. When the BSxT1−x thin film is deposited at Rp = 150 W and room temperature, the deposition rate decreases with the increasing working pressure (Wp) and O2/(O2 + Ar) ratio (Or). The refractive index of the BSxT1−x thin films is between 2.1 and 2.3, which shows that the variation of working pressure is not very significant. The dielectric constant of the BSxT1−x thin films increases with the Rp increasing from 100 to 150 W and decreases above 150 W. The leakage current density of the BS0.15T0.85 thin films nearly displays the ohmic behavior when the electric field is below 50 kV/cm. The conduction mechanism of the BS0.15T0.85 thin films involves the Schottky emission (SE) and Poole–Frenkel emission (PF) models. The BSxT1−x thin film shows a ferroelectric characteristic in the polarization-electric field plot. more...

Microfiltration (MF) coupled with pretreatment by coagulation was adopted in the treatment of chemical mechanical polishing (CMP) wastewater from IC manufacturing plants, containing high concentrations of silica. Poly-aluminium chloride (PACl) was the coagulant, while the cationic polyacrylamide (PAA) was the flocculant aid. Preliminary tests were performed with the raw CMP wastewater in order to determine the optimal coagulation condition for subsequent microfiltration. Analysis of the particle size distribution shows that nearly all silica particles were enlarged from nano scale to at least 4 μm in diameter after the pre-treatment. The pre-treated wastewater was then filtered through a polytetrafluoroethylene (PTFE) membrane with a pore size 0.5 μm at a constant vacuum pressure. Trace amounts of PAA in addition to the PACl coagulation can effectively increases the permeate flux. more...

The magnetic method can be efficiently applied to archaeological investigation especially when the S/N ratio is enhanced appropriately. This study presents a model experiment and field examples of magnetic exploration in archaeology. By using appropriate measuring processes and filtering methods, the conventional and more recent magnetic prospecting techniques are successfully applied to the very shallow, small-scale investigations, which are used to locate and map archaeological targets. We focus on mapping the buried slate caskets in the alluvial environment, which is the most commonly encountered and readily preserved ones at the archaeological sites of Taiwan. The gradiometry and the inferred derivatives may resolve individual anomalies. Locations of the maxima determined by the 3-D analytic signals can be used to describe the outlines of the bodies that cause the anomalies. Furthermore, the susceptibility was very successful in mapping near-surface targets at the Chubin site. The magnetic results of the example at the Hutzushan site, compared to the GPR survey carried out by previous investigators, indicate that the GPR anomalies may be caused by other sources. The magnetic response of a casket can be displayed in various ways, depending on the pole distribution of the casket, the geometry, the magnetization direction and the orientation of buried casket. The processing methods may improve the data resolution, but precautions must be taken for the artifacts. more...

Background: Diabetes mellitus is known to exacerbate bacterial infection, but its effect on the severity of viral infection has not been well studied. The severity of thrombocytopenia is an indicator of the severity of dengue virus infection. We investigated whether diabetes is associated with thrombocytopenia in dengue-infected patients. Methods: We studied clinical characteristics of 644 patients with dengue infection at a university hospital during the epidemic on 1 June 2002 to 31 December 2002 in Taiwan. Platelet counts and biochemical data were compared between patients with and without diabetes. Potential risk factors associated with thrombocytopenia were explored using regression analyses. Results: Dengue-infected patients with diabetes had lower platelet counts than patients without diabetes during the first three days (54.54 ± 51.69 vs. 86.58 ± 63.4 (p ≤ 0.001), 43.98 ± 44.09 vs. 64.52 ± 45.06 (p = 0.002), 43.86 ± 35.75 vs. 62.72 ± 51.2 (p = 0.012)). Diabetes mellitus, death, dengue shock syndrome (DSS) and dengue hemorrhagic fever (DHF) and increased glutamic-pyruvate transaminase (GPT) levels were significantly associated with lower platelet counts during the first day of hospitalization for dengue fever with regression β of −13.981 (95% confidence interval (CI) −27.587, −0.374), −26.847 (95% CI −37.562, −16.132), and 0.054 (95% CI 0.015, 0.094) respectively. Older age, hypoalbuminemia, and hypertriglyceridemia were independently correlated with thrombocytopenia in dengue patients with or without diabetes with regression β of −2.947 (p = 0.004), 2.801 (p = 0.005), and −3.568 (p ≤ 0.001), respectively. Diabetic patients with dengue had a higher rate of dengue hemorrhagic fever (DHF)/dengue shock syndrome (DSS) than non-diabetic patients. They also had lower blood albumin, were older, and higher triglyceride levels. Older age, hypoalbuminemia, and hypertriglyceridemia were independently correlated with thrombocytopenia in dengue patients. Conclusions: Dengue patients with diabetes tended to have more severe thrombocytopenia and were more likely to have DHF/DSS. Older age, hypoalbuminemia, and hypertriglyceridemia were independently associated with more severe thrombocytopenia in dengue patients. more...

This paper presents a basic database for the joint actions of 44 binary mixtures of various organic toxicants on Escherichia coli. The multiple toxicity behaviors observed from the E. coli organisms were analyzed and compared with previous works based on the Microtox tests. The two kinds of tests produced quite different responses, in terms of the joint action mode and the sum of toxic units, to various organic mixtures. However, detailed analyses with the considerations of the chemical's mechanisms of toxicity and the slope of toxicant's dose-response curve have revealed several general criteria for the prediction of combined effects of organic toxicants. First, for both reactive and non-reactive toxicants, either additive or less than additive (antagonistic) joint actions will be observed for chemicals of the same mechanism of toxicity. Second, the mixture of reactive toxicants with different mechanisms is the only category of organic mixtures associated with frequent observations of synergism. Third, greater-than-additive (synergistic) effects are inherently associated with toxicants having flat dose-response curves. Less than additive effects are, however, mainly related to a chemical's display steep dose-response curves. Model analyses indicate that the observed synergistic effects are due to response addition or response multiplication joint actions. Hence, most of the synergistic joint actions are non-interactive in nature and are governed by the dose-response relationships of individual toxicants. more...

Batch-type algal toxicity tests were conducted to evaluate the low toxic effects of metal toxicants. Both the no-observed-effect concentration (NOEC) and the effective concentration at 10% inhibition (EC10) were calculated and compared. The results of this study indicate that, for algal toxicity tests, NOEC offers better protection to the test organisms than EC10. In addition, the consistency of NOEC is found to depend on the response endpoints measured. A cut-off-value approach is proposed to determine whether NOEC or EC10 should be chosen for estimating low toxic effects. For a specific toxicity test, the average cut-off value directly indicates the magnitude of the square root of the within-group-variance. A precise test associated with small within-group-variances also produces relatively small average cut-off value (say, less than 10% of the growth reduction). This average value provides useful information on the minimum protection that can be offered by the NOEC. more...

The aim of the present study is to compare the effects of the mean cell volume (MCV) of algal inoculum to the sensitivity and reproducibility of the toxicity test. Two sets of experiments were conducted using inoculums with the MCV equal to 60 μm3/cell and 40 μm3/cell, respectively. The initial cell densities, however, were kept the same at 10,000 cells/mL. The results show that larger MCV of the inoculum results in greater EC50 values. Similar observations and conclusions were obtained from comparisons based on NOEC values. Thus, MCV of the inoculum significantly influences the observed toxic response in terms of EC50 and NOEC values. It is also evident that, there is a significant increase in the test variability if the MCV is not controlled properly. This study reports that standardizing the initial mean cell volume of algal culture can improve inter-laboratory and intra-laboratory precision. Furthermore, replacing the EC50 values by the calculated exposure values (EE50) can reduce the variability in data due to differences in the MCV of the inoculum. more...

In this study, we compare the no-observed-effect concentrations (NOECs) based on different response parameters, using batch and continuous algal toxicity tests. For both batch and continuous tests, parameters based on total cell volume (TCV) were found to be less sensitive than those related to cell densities. The above observation mainly occurred because, under the stresses from metal toxicants evaluated in this and a previous study, the mean cell volume (MCV) of algae increased considerably. The increase of MCV compensates for the effects brought about by the reduction in cell density and eventually results in less variation in TCVs. This study shows that parameters based on cell density are quite sensitive and ideal for the estimation of NOECs. In addition, comparison of the NOEC values derived from different culture techniques shows that the continuous method generally yields lower NOEC values than that obtained by the batch tests. The results of this study also indicate that the NOEC provides more protection to the test organism than the effective concentration at 10% growth reduction (EC10). For toxicity test methods that produce small variations among replicates, the NOEC is still a good indicator of low toxic effect. Furthermore, for the continuous algal toxicity test, a relatively simple approach is proposed to determine the NOEC values based on the algal culture's control charts. The proposed method produced identical results as those based on conventional hypothesis-testing methods. more...

In this study, we compare individual and combined responses of metal toxicants, on Selenastrum capricornutum, using batch and continuous techniques. The batch test is characterized by its saturated nutrient status for algal growth and, on the other hand, the continuous test is conducted at a nutrient-limiting condition. The two test methods depict completely different relationships in relative toxicity. In addition, the batch tests seriously underestimate the toxicity of metal mixtures containing lead. The above phenomena can be attributed to the surplus amounts of a limiting nutrient (phosphorus) and chelators in the growth medium. Since algae in the field are grown under low concentrations of nutrients and chelators, the results presented herein suggest that the significance and adequacy of current algal toxicity test protocols should be carefully reviewed. more...

Responses of Selenastrum capricornutum to cadmium in a chemostat are evaluated under various test conditions defined by the nitrogen to phosphorus ratio, phosphate strength, dilution rate, and ethylenediaminetetraacetic acid content. Based on the test results, these parameters were optimized to achieve superior test sensitivity. This continuous system was also modified to allow testing on a weekly basis. The performance of the modified testing technique was evaluated, employing six different metal toxicants. Compared with batch test results reported by other researchers and our own experiment, the continuous test achieved superior sensitivities and reproducibility. The test method presented in this study is believed to be an ideal technique both for research and regulatory purposes. more...

The physical properties of PVA-borax aqueous solutions with a PVA concentration near the overlap concentration and various borax concentrations were observed using dynamic light scattering and dynamic viscoelastic measurements. It had been proposed by Leibler et al. that the structure of PVA-borate complex in dilute aqueous solution strongly depends on: (1) excluded volume effect of polymers; (2) the intra- and inter-molecular crosslink reactions between di-diol of PVA and borate ion; (3) the charge repulsion among borate ions bound on the PVA molecules; (4) the screen effect of the free Na + ions on the negative charge of PVA-borate complex molecules. Based on the experimental data and the model of Leibler et al. , the structures of PVA-borate complexes near the overlap concentration in aqueous solutions were proposed. more...

Responses to copper and sodium pentachlorophenate at various nutrient concentrations, up to COD=1500 mg/l, were compared in different types of microbial cultures : Escherichia coli and activated sludge. In the E coli. culture, effective concentration at 50% inhibition varies from 0.745 mg/l to 11.56 mg/l (copper) and from 1.963 mg/l to 8.163 mg/l (sodium pentachlorophenate) when COD concentrations change from 30 mg/l to 1500 mg/l, respectively. For the activated sludge, however, EC50 remains stable, indicating toxicity is independent of nutrient status. This phenomenon is mainly related to the species composition which determines the correlation coefficient. Results in this study indicate that the influence of the type of microbial cultures is a crucial factor in determining microbial growth dynamics. more...

In this study we evaluated the joint actions of cyanogenic toxicants with other organic chemicals using Microtoxx® tests. Experimental results indicated that greater than additive effect seldom occurred when these chemicals were mixed with nonreactive toxicants. However, the likelihood of synergistic effects exceeded 30% when reacting with a reactive chemical. Among the cyanogenic toxicants investigated in this study, malononitrile, lactonitrile, and α-hydroxy-isobutyronitrile have an approx. 50% likelihood of acting via synergism mode with other reactive toxicants. On the other hand, the joint actions related to acetonitrile and allyl cyanide are either additive or less than additive. Moreover, the likelihood of encountering synergistic effects markedly increases if the slopes of the dose–response curves for the two chemicals tested are small. Therefore, slope and certain characteristics of a chemical structure can apparently be used as indices to assess the potential hazard for a specific organic mixture. Furthermore, the complex joint action exerts a certain deterministic influence over the joint action mode of cyanogenic toxicants. This type of joint action, which quite frequently leads to an obvious antagonistic or even detoxification phenomena, could have some useful toxicological and pharmacological applications. Lastly, estimating the mixture toxicity on the basis of the concentration addition model is not always appropriate considering the high percentage of cases in this study showing synergism. more...

Metal toxicity on selenastrum capricornutum were examined by batch culture and chemostat culture system. EC50 values under nutrient‐limited condition and saturated condition were compared. The two EC5Os differed by a factor of 10.6 for Cd in batch test, and differed by a factor of 6.5 in continuous test. Both batch and continuous test results indicate that inhibition on algal growth is more severe under nutrient‐limited conditions compared to that under near saturation conditions. Strong correlation, as characterized by the correlation coefficient ρ, were found between the activation level (nutrient requirement) and the tolerance of microorganisms to the toxicant. ρ is equal to 0.9 for the case of Cd in batch test and 0.6 in continuous test. The theory in this study provides generally good estimations to the dose‐response relationship at limiting nutrient conditions. The study indicate that nutrient conditions constitute an important factor in algal toxicity tests. more...

This study evaluated the toxicity of binary mixtures of reactive toxicants using the Microtox test. Greater than additive effects were quite frequently observed (18%) among chemicals with different mechanisms of toxicity, and some of them were severely synergistic. The concentration-addition model, therefore, may not be appropriate for estimating the multiple toxicity of mixtures containing reactive toxicants. The slope of a chemical's concentration-response curve was found to play an important role in determining the mode of joint actions, which could be related to the complex joint action identified earlier. The results of this study have been summarized into several relationships that can be used to estimate the potential risks for mixtures with unknown toxicity. 0 7996 by John Wiley & Sons, Inc. more...

Toxicity of binary mixtures of organic chemicals was evaluated using the Microtox test, in order to derive a more realistic approach for predicting mixture toxicity. Both additive and less than additive effects were found from binary mixtures of nonreactive toxicants. Concentration addition can be expected between two nonreactive chemicals, provided that the requirement of parallel dose—response curves is fulfilled. The study also identified the conditions for a complex—type joint action to take place. Finally, experimental isobolograms were analyzed based on a bivariate toxicity model to provide a rational estimation of model parameters. The isobolograms and the additive indices generated by this study can be used to predict the combined toxic effects from various organic mixtures. © by John Wiley & Sons, Inc. more...